Method and device for coloring magnetizable articles of mass production



April 2, 1940. w. MAGEYNER ET AL 2,195,731

METHOD AND DEVICE FOR COLORING MAGNETIZABLE ARTICLES OF MASS PRODUCTION Filed July 9, 1938 INVENTOR WWW/ M9 Y am A. W

/ w" HTTORNEYS Patented Apr. 2, 1940 METHOD AND DEVICE FOR COLORING MAG- NETIZABLE ARTICLES 0F MASS PRODUC- TION Wilhelm Magener and Otto R. Barth, Berlin,

Germany von Mikovnyi said Barth asslgnor to Willibald Application July 9, 1938, Serial No. 218,474 In Germany July 17, 1937 3 Claims.

Our invention relates to the coloring of metal articles of mass production, such as snap fasteners, safety pins, and the like, as far as these articles consist of magnetizable material.

A suitable way of coloring articles of the above kind is employing the well-known spraying method. However, when applying this method to articles of such smallness and lightness, a number of difficulties arise. The air current from the spray gun easily whirls around the articles, thus scratching and wiping the freshly deposited color, and also tends to blow them off the spray rack. A prerequisite for a satisfactory coloring of small articles by spraying, therefore, is to attach them to the supporting rack in order to prevent them from being moved by the spray current. This result could be obtained by providing the surface of the rack with pins or other holding means on which the objects to be colored are to be placed by hand. It is, however, also necessary to reverse the articles on the supporting rack after the upper surface has been colored, in order to now spray the other side. It is evident that such a method which requires repeatedly manipulating each individual article involves expense which in the case of mass prodacts are liable to render the products u marketable.

The object of our invention consists in providing a method and apparatus for spray-coloring articles of mass production, in particular such as aforementioned, in an easy and inexpensive way which obviates the above difficulties.

The method according to our invention comprises the' following sequence of steps. At first the articles to be colored are placed on a magnetizable rack or table in proper position for spraying. Then the rack is magnetized, thereby firmly attaching the articles to the supporting surface of the rack. Now the upper side of the articles is colored by spraying them with a coloring liquid such as paint, varnish, lacquer or the like. After drying of the color, a second magnetizable rack is placed upon the articles so as In the following, the invention is further elucidated with reference to the accompanying drawing showing a part-sectional front elevation of a device for carrying out the aforementioned method.

The device contains a base F having two insulating frames or beds" B1 and B2 firmly attached thereto. Each bed carries a magnetizable plate P1 and P: respectively, each being provided with a magnetizing winding W1 and W2 respectively. Plate P: is mounted to a lever L pivoted about shaft A on frame F. A handle H forming part of lever L allows removing plate P2 from bed B2 and tilting it 180 through the position indicated by broken lines, until it reaches plate P1 and rests on top of this other plate.

The plates Pi and P2 are of equal size and consist of iron or another ferromagnetic material of high permeability. In the case of a device for spray-coloring snap fasteners or safety pins,

for instance, iron plates having a thickness of 2 to 3 mm. may be used. The outer surface of each plate forming the rack surface proper, is ground. The windings W1 and W: are connected by conductors C1 and C: through a selective switch S with conductors C leading to a current source. Switch S has three operating positions, one for cutting off the current supply, one for energizing winding W1, and the third for energizing winding We. Therefore, only one of the plates can be magnetized at a time.

The device is operated as follows. In the position of rest shown in the drawing, a multitude of articles to be colored, for instance 2,000 to 3,000 snap fasteners, are poured on plate P1 and then evenly spread over the surface of the plate so that all the fasteners lie flatly side by side. Now plate P1 is magnetized by operating switch S. The fasteners, represented in thedrawing by dashes D, thus are firmly secured in proper position for spraying. Now the top side of the fasteners is painted by means of a spray gun. After finishing the spraying and after drying of the paint, the plate P2 by means of handle H is turned over to plate P1 until its surface contacts the snap fasteners. Now switch S is again actuated to disconnect winding W1 and to energize winding W2. The effect is that now the fasteners while maintaining their proper position are released from plate P1 and attached to plate P2. If now plate P2 is turned back to resume the original position shown in the drawing, the snap fasteners lie properly on this plate now offering their unpainted surface to the spray gun. After finishing the coloring, the current is switched off and the snap fasteners are removed from plate P2.

for instance by again tilting the plate and thereby throwing the fasteners into a collecting box. The device is now ready for another spray. The coloring of safety pins and other small magnetizable objects is effected in the same way.

We claim:

1. The device for spray-coloring magnetizable articles such as snap fasteners, safety pins and the like, comprising a stationary frame, a magnetizable spray rack firmly mounted on said frame, a second magnetizable spray rack pivoted on said frame so as to be movable from a working position onto said first rack, and means for alternatively magnetizing said racks.

2. The device for spray-coloring magnetizable articles such as snap fasteners, safety pins and the like, comprising two magnetizable racks for carrying the articles to be colored, each of said racks comprising a plate of ferromagnetic material and a winding for magnetizing said plate, said racks being designed to allow placing one of them on top of the other so as to have their carrying surfaces facing each other, electric means for connecting said windings with a current source, and a selective switch forming part of said means for alternately energizing said windings.

3. The method of spray-coloring magnetizable articles such as snap fasteners, safety pins and the like, with the aid of two magnetizable spray racks, comprising the steps of placing a multitude of said articles on one of said racks, magnetizing said rack so as to firmly attach said articles to said rack, spray-coloring the upper side of said articles, placing said other rack on said articles, demagnetizing said first rack and magnetizing said second rack so as to now attach said articles on their colored side to said second rack, removing said second rack from said first rack, again spraying said articles for coloring their other side, and releasing said articles by demagnetizing said second rack.

WILHELM MAGENER OTTO R. EARTH. 

